Since 2006, he had written and shot for his own blog, Amateur Chemist, and publications including Stereogum and the OC Weekly several times a week. One could hardly go to a photo pit at a marquee concert in Southern California without running into him. He was one of the area's most tireless and enthusiastic music fans, and even after his diagnosis, he continued shooting and covering bands until October (his final concert shoot was for Depeche Mode in Los Angeles).

He chronicled his life in an OC Weekly blog, Last Shot, where music reviews wove into his larger existential thoughts on his condition in his waning days. On Sept. 26, he wrote that he would be halting intensive treatment and begin preparing for the end of his life -- but he didn't stop writing or shooting.

Many of his favorite musicians returned the affection, giving him exclusive backstage glimpses and acknowledgment onstage. Trent Reznor of Nine Inch Nails, one of Youssef's favorite bands, turned a recent Las Vegas show into an uplifting, heartwrenching tribute, dedicating NIN's song "In This Twilight" to him.

Last month, Justin Bieber recruited R. Kelly to help him sex up his sound with "PYD," a steamy slow jam in which the teen-pop superstar provides a thorough accounting of the appliances and furniture pieces on which he plans to, er, romance a lady friend. (Kelly, meanwhile, reports that he's "been...

During my recent interview with author Mark Lewisohn about his monumental new biography of the Beatles, “Tune In: The Beatles: All These Years,” he very briefly let slip a comment that might qualify as favoritism, something that doesn’t figure into the book itself, an even-handed, deeply researched...